Materials Data on U(BiO2)4 by Materials Project

Abstract

U(BiO2)4 crystallizes in the orthorhombic Immm space group. The structure is three-dimensional. U4+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are four shorter (2.30 Å) and four longer (2.41 Å) U–O bond lengths. There are two inequivalent Bi3+ sites. In the first Bi3+ site, Bi3+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Bi–O bond distances ranging from 2.34–2.47 Å. In the second Bi3+ site, Bi3+ is bonded to six O2- atoms to form a mixture of distorted corner and edge-sharing BiO6 octahedra. The corner-sharing octahedral tilt angles are 59°. There are a spread of Bi–O bond distances ranging from 2.28–2.50 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded to four Bi3+ atoms to form a mixture of corner and edge-sharing OBi4 tetrahedra. In the second O2- site, O2- is bonded to four equivalent Bi3+ atoms to form a mixture of corner and edge-sharing OBi4 tetrahedra. In the third O2- site, O2- is bonded to two equivalent U4+ and two equivalent Bi3+ atoms to form a mixture of corner and edge-sharing OU2Bi2 tetrahedra. In the fourth O2- site, O2- is bonded to two equivalent U4+ and two equivalent Bi3+ atoms to form OU2Bi2 tetrahedra that share corners with fourteen OBi4 tetrahedra and edges with five OU2Bi2 tetrahedra.